The copy threshold option is used to prevent the write response performance for DRS-VOLs from being degraded due to overload by the copy processing of a replication program product that runs on the background.
You can enable the copy threshold option to suppress the background copy processing in the following replication program products:
- ShadowImage (SI) and ShadowImage for Mainframe(SIz)
- Thin Image Advanced (TIA)
- Volume Migration (VM)
- TrueCopy (TC) and TrueCopy for Mainframe (TCz)
- Universal Replicator (UR) and Universal Replicator for Mainframe (URz)
- Global-active device (GAD)
- Compatible FlashCopy® V2 (FCv2) and Compatible FlashCopy® SE (CFCSE)
| Setting | Program product | Operation |
|---|---|---|
| OFF | SI, SIz, VM, FCv2, CFCSE | As per the SOM 467 setting. |
| TC, TCz, GAD | As per the SOM 689 setting. | |
| UR, URz | As per the SOM 690 setting. | |
| TIA | When the cache write pending rate of the MP unit in the CLPR of the copy target is 60% or higher, background copy processing is suppressed. | |
| ON | SI, SIz, TIA, VM, TC, TCz , GAD, UR, URz | The background copy processing stops when the cache write pending (WP) rate of the MP unit in the copy target CLPR is 35% or higher. |
| FCv2, CFCSE | The background copy processing slows down when the cache write pending (WP) rate of the MP unit in the copy target CLPR is 35% or higher. |